Systems and methods for variable injection flow

ABSTRACT

Systems and methods for controllably variable fluid flow are disclosed that provide the ability to modify the effective cross-sectional area of the fluid delivery conduit available for fluid flow. Accordingly, selective control of these configurations allows fluid flow to be regulated as desired while the fluid delivery pressure remains the same. Additional configurations provided herein allow for the selective manipulation of a footprint or therapeutic pattern achievable with the medical device during a single procedure, negating the need for the removal and insertion of multiple devices to achieve the same variations in treatment geometry or characteristics.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation of U.S. utility patent applicationSer. No. 13,300,931, filed Nov. 21, 2011, entitled SYSTEMS AND METHODSFOR VARIABLE INJECTION FLOW, which application is related to and claimspriority to U.S. Provisional Application Ser. No. 61,552,527, filed Oct.28, 2011, entitled SYSTEMS AND METHODS FOR VARIABLE INJECTION FLOW, theentirety of which is incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

n/a

FIELD OF THE INVENTION

The present invention relates to systems and methods of use thereof forcontrolled fluid delivery in medical devices to provide safe andeffective treatment.

BACKGROUND OF THE INVENTION

Minimally invasive devices, such as catheters, are often employed formedical procedures, including those involving mapping, ablation,dilation, and the like. For example, a thermal diagnostic or treatmentprocedure may involve permanently and/or temporarily exchanging thermalenergy with a targeted tissue region, such as creating a series ofinter-connecting or otherwise substantially continuous lesions in orderto electrically isolate tissue believed to be the source of anarrhythmia. An example of a thermal mechanism for diagnosis andtreatment is a cryogenic device that uses the energy transfer derivedfrom thermodynamic changes occurring in the flow of a cryogentherethrough to create a net transfer of heat flow from the targettissue to the device. The quality and magnitude of heat transfer isregulated in large part by the device configuration and control of thecryogen flow regime within the device.

Structurally, cooling can be achieved through injection of high pressurerefrigerant through an orifice. Upon injection from the orifice, arefrigerant may undergo two primary thermodynamic changes: (i) expandingto low pressure and temperature through positive Joule-Thomsonthrottling, and (ii) undergoing a phase change from liquid to vapor,thereby absorbing heat of vaporization. The resultant flow of lowtemperature refrigerant through the device acts to absorb heat from thetarget tissue and thereby cool the tissue to the desired temperature.

The efficacy of a thermal exchange procedure may be substantiallyaffected by the fluid flow through the device as well as the thermalconductivity between a device and the tissue site. To provide shortertreatment durations and increased efficacy for the particular treatmentprovided, it is desirable to optimize the heat transfer between thespecific tissue to be treated and the cryogenic element or device. Suchoptimization may include providing accurate and precise fluid deliverythrough a selected device to achieve the desired thermal affect in thephysiological location being treated. Such physiological locations ofteninclude numerous environmental factors that can constantly change,resulting in fluctuating thermal conditions arising between the tissueand the device. For example, blood or other body fluids passing throughthe vicinity of the thermal device can reduce the quality of thermalexchange with the targeted tissue, which can then necessitate additional“cooling power” or refrigerant flow in the case of cryogenic treatmentsin order to complete the desired treatment.

Accordingly, it is desirable to provide systems and methods of usethereof that provide accurate and precise control over fluid delivery toand through such devices in order to optimize the efficacy of the devicein a physiological environment.

SUMMARY OF THE INVENTION

The present invention advantageously provides systems and methods of usethereof that provide accurate and precise control over fluid delivery toand through such devices in order to optimize the efficacy of the devicein a physiological environment. In particular, a medical device isprovided, including a catheter body defining a distal portion; a fluiddelivery conduit defining an outlet in the distal portion of thecatheter body, an elongate member movably disposed within at least aportion of the fluid delivery conduit to selectively obstruct a portionof the fluid delivery conduit to modulate fluid flow through the outlet.The medical device may define a fluid exhaust lumen within the catheterbody, the fluid delivery conduit may define a tapered diameter, and/orthe elongate member may be longitudinally movable with respect to thetapered diameter. The elongate member may include a plug movablypositionable about the outlet, where the plug may include a taperedcross-section and/or be substantially spherical. The elongate member maybe constructed from a shape memory material that transitions in responseto a thermal and/or electrical load. The fluid delivery conduit maydefine a plurality of outlets in the distal portion, and the elongatemember may be movable to selectively obstruct the plurality of outlets.The medical device may include a cryogenic fluid source in fluidcommunication with at least one of the fluid delivery conduit orelongate member.

A method of regulating fluid flow through a catheter is provided,including delivering a fluid to a fluid delivery conduit disposed withina portion of the catheter; and moving a rod within a portion of thefluid delivery conduit to at least partially obstruct a portion of thefluid delivery conduit to regulate fluid flowing therethrough. The fluiddelivery conduit may define a tapered section, and moving the rod mayinclude moving the rod with respect to the tapered section.

A medical device is provided, including a catheter body defining adistal portion; a fluid delivery conduit defining an outlet in thedistal portion of the catheter body, and a deformation element withinthe catheter body, the deformation element controllably movable todeform a portion of the fluid delivery conduit to affect fluid flowtherethrough. The deformation element may be movable substantiallyperpendicularly to the fluid delivery conduit to depress a portion ofthe fluid delivery conduit and/or may be rotatable about the fluiddelivery conduit to depress a portion of the fluid delivery conduit.

A method of regulating fluid flow through a catheter is disclosed,including delivering a fluid to a first conduit disposed within aportion of the catheter; and mechanically deforming a portion of thefirst conduit to controllably regulate fluid flowing therethrough.

A method of controlling fluid delivery in a medical device is provided,including movably positioning a fluid delivery conduit within a deliverymanifold in the medical device, the fluid delivery conduit defining afirst plurality of openings and the delivery manifold defining a secondplurality of openings; introducing a fluid into the fluid deliveryconduit; moving the fluid delivery conduit to a first position where thefirst plurality of openings is substantially aligned with the secondplurality of openings to direct fluid through the first and secondplurality of openings; and moving the fluid delivery conduit to a secondposition where the second plurality of openings are substantiallyobstructed by the fluid delivery conduit, and at least one of theplurality of first openings is positioned outside the manifold such thatfluid is directed through the at least one of the plurality of firstopenings. The second plurality of openings may be asymmetricallydisposed about a longitudinal axis of the manifold, the fluid mayinclude a cryogenic fluid, and/or the medical device may include athermally-transmissive region proximate the delivery manifold, such as aballoon or an electrode.

A medical device is disclosed, including an elongate body defining adistal portion; and a unitary distal insert coupled to the distalportion, the distal insert defining: a first lumen extendingtherethrough, a second lumen coaxial with the first lumen, and aplurality of openings in fluid communication with the second lumen. Theunitary distal insert may define a collar and the medical device mayinclude one or more steering elements coupled to the collar. The medicaldevice may include a thermally-transmissive region substantiallyenclosing the distal insert and/or a rod movably positionable with aportion of the first lumen.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present invention, and theattendant advantages and features thereof, will be more readilyunderstood by reference to the following detailed description whenconsidered in conjunction with the accompanying drawings wherein:

FIG. 1 is an illustration of an example of a medical device and controlunit of a medical system constructed in accordance with the principlesof the present disclosure;

FIG. 2 is a cross-sectional view of a distal portion of the medicaldevice of FIG. 1;

FIG. 3 is a perspective view of the distal portion shown in FIGS. 1-2;

FIG. 4 is another example of a distal portion of the medical deviceshown in FIG. 1;

FIG. 5 is another cross-sectional view of a distal portion of themedical device of FIG. 1 or 4;

FIG. 6 is an illustration of an example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 7 is an illustration of another example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 8 is an illustration of yet another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 9 is an illustration of still another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 10 is an illustration of another example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 11 is an illustration of yet another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 12 is an illustration of still another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 13 is an illustration of another example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 14 is an illustration of still another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 15 is an illustration of yet another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 16 is an illustration of another example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 17 is an illustration of still another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 18 is an illustration of yet another example of a fluid deliverytube configuration for a medical device in accordance with theprinciples of the present disclosure;

FIG. 19 is an illustration of another example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 20 is an illustration of another example of a fluid delivery tubeconfiguration for a medical device in accordance with the principles ofthe present disclosure;

FIG. 21 is an illustration of another example of a medical device inaccordance with the principles of the present disclosure; and

FIG. 22 is an illustration of another example of a medical device inaccordance with the principles of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

The present invention advantageously provides systems and methods of usethereof that provide accurate and precise control over fluid delivery toand through such devices in order to optimize the efficacy of the devicein a physiological environment. Referring now to the drawing figures inwhich like reference designations refer to like elements, an embodimentof a medical system constructed in accordance with principles of thepresent invention is shown in FIG. 1 and generally designated as “10.”The system 10 generally includes a medical device 12 that may be coupledto a control unit 14. The medical device 12 may generally include one ormore treatment regions for energetic or other therapeutic interactionbetween the medical device 12 and a treatment site. The treatmentregion(s) may deliver, for example, cryogenic therapy, radiofrequencyenergy, or other energetic transfer with a tissue area in proximity tothe treatment region(s), including cardiac tissue.

Continuing to refer to FIG. 1, the medical device 12 may include anelongate body 16 passable through a patient's vasculature and/orproximate to a tissue region for diagnosis or treatment, such as acatheter, sheath, or intravascular introducer. The elongate body 16 maydefine a proximal portion 18 and a distal portion 20, and may furtherinclude one or more lumens disposed within the elongate body 16 therebyproviding mechanical, electrical, and/or fluid communication between theproximal portion of the elongate body 16 and the distal portion of theelongate body 16, as discussed in more detail below.

The medical device 12 may further include a fluid delivery conduit 22traversing at least a portion of the elongate body 16 and distal portion20. The delivery conduit 22 may be coupled to or otherwise extend fromthe proximal portion 18 of the elongate body 16. The fluid deliveryconduit 22 may be flexible, constructed from a shape memory material(such as Nitinol), and/or include other controllably deformablematerials that allow the fluid delivery conduit 22 to be manipulated forselective fluid flow control as described herein. The fluid deliveryconduit 22 may define a lumen therein for the passage or delivery of afluid from the proximal portion of the elongate body 16 and/or thecontrol unit 14 to the distal portion 20 and/or treatment region of themedical device 12. The fluid delivery conduit 22 may further include oneor more apertures or openings therein providing dispersion or directedejection of fluid from the lumen to an environment exterior to the fluiddelivery conduit 22.

The elongate body 16 may also define or otherwise include an exhaustlumen 24 in fluid communication with the distal portion 20, proximalportion 18, and/or control unit 14 to facilitate circulation or removalof fluid within the medical device 12. A guide wire lumen may also bedisposed or otherwise included in the elongate body 16.

Now referring to FIGS. 1-3, the medical device 12 may include a distalinsert 26 coupled to the elongate body 16, where the distal insert 26provides multiple anchoring or connection points for steeringmechanisms, electrical signal wires, and/or fluid dispersion and removalfeatures. For example, the distal insert 26 may include a unitary bodyhaving a proximal segment 28 engageable with the elongate body 16. Theproximal segment 28 may define a plurality of ridges or angled teeth 30aiding in securing or anchoring the distal insert 26 within a portion ofthe elongate body 16. The distal insert 26 may also define a collar 32adjacent the proximal segment 28, the collar 32 having a larger diameterthan the proximal segment 28 such that the collar 32 can be sealed tothe elongate body 16. As shown in FIG. 2, the collar 32 may furtherdefine one or more anchoring points 34 for a temperature sensor,steering wire, and/or electrical signal wire. The distal insert 26 mayfurther include or define a distal segment 36 on an opposite side of thecollar 32, where the distal segment 26 defines a fluid dispersionchannel 38 and a fluid exhaust channel 40 in fluid communication withthe fluid delivery conduit 22 and exhaust lumen 24, respectively. Forexample, the fluid dispersion channel 38 may extend longitudinallythrough the distal segment 36 and open at an aperture 42 at a distaldirection at a tip or distal-most face of the insert 26. The fluidexhaust channel 40 may include one or more openings 44 on an exteriorsurface and/or transverse to the fluid dispersion channel 38 locatedproximal to the aperture 42 and/or in proximity to the collar 32.

The medical device 12 may further include a thermally-transmissiveregion 46 at the distal portion 20 that provides for energy exchangebetween the medical device 10 and targeted tissue region. Thethermally-transmissive region 46 may include, for example, a thermally-and/or electrically-conductive shell (as shown in FIGS. 1 and 3) thatsubstantially surrounds the distal segment 36 of the distal insert 26.The shell may be coupled to the collar 32 and/or elongate body 16 toprovide a fluid-tight seal. The shell may also be in communication withthe control unit 14 to send and/or receive diagnostic or therapeuticsignals or energy to and from a targeted tissue region. Thecommunication may be established or facilitated by one or more wiresanchored to the collar 32 of the distal insert 26, for example.

Referring now to FIG. 4, the thermally-transmissive region 46 mayinclude an expandable element or balloon at the distal portion 20 of theelongate body 16. The expandable element may be coupled to a portion ofthe elongate body 16 and/or the distal insert 26. The expandable elementmay further be coupled to a distal tip 48 that may be attached to one ormore steering elements (not shown) to allow manipulation of theexpandable element. The distal tip 48 may also define a guide wire lumentherethrough. The expandable element defines an interior chamber orregion that contains coolant or fluid dispersed from the fluid deliveryconduit 22, and may be in fluid communication with the exhaust lumen 24for the removal of dispersed coolant from the interior of the expandableelement. The expandable element may further include one or more materiallayers providing for puncture resistance, radiopacity, or the like.

Referring now to FIGS. 5-19, a number of exemplary configurations foraccurately and precisely manipulating fluid flow through the fluiddelivery conduit of the medical device are shown. These configurationsmay be used, for example, in proximity to a distal portion 20 and/or athermally-transmissive region 46 of the medical device 12 to achievedesirable therapeutic or diagnostic effects, which may include varyingdegrees of thermal interaction with an adjacent tissue region. Forexample, as shown in FIGS. 5-7, the medical device 12 may include asecondary elongate body or rod 50 positioned within a portion of thefluid delivery conduit 22 and/or the fluid dispersion channel 38 of thedistal insert 26. The rod 50 may be selectively and controllably movableto obstruct or restrict a portion of the diameter of the fluid deliveryconduit 22 or fluid dispersion channel 38 to thus modulate fluid flowingtherethrough. Alternatively, the rod 50 may be constructed from a shapememory allow that predictably lengthens and shortens in response to adesignated thermal or electrical load. Accordingly, the elongate body 50may be controllably manipulated into a desired length or width withinthe fluid delivery conduit 22 through the application or removal of athermal or electrical load. The thermal or electrical load may becontrollable and/or otherwise provided at a proximal portion of themedical device 12 and/or from the control unit 14.

As shown in FIGS. 6-7, the fluid delivery conduit 22 or fluid dispersionchannel 38 may define a tapered diameter or stepped decrease in diameterin proximity to where the rod 50 is positioned or slidably movable tofurther facilitate changes in fluid flow rate and/or volume due tomovement of the rod 50 within the lumen.

Now referring to FIGS. 8-10, a plug 52 may be movably disposed within aportion of the fluid delivery conduit 22 to selectively obstruct aportion of an outlet 54 of the fluid delivery conduit. The plug 52 mayinclude a number of geometric variations to achieve the desiredmodulation of fluid flow through the delivery conduit 22. For example,as shown in FIG. 8, the plug 52 may have a substantially rectangularshape oriented transversely to a longitudinal axis of the fluid deliveryconduit 22. The plug 52 may also have a trapezoidal or angled shape toprovide progressively increased or decreased fluid flow depending on theposition of the plug 52, as shown in FIG. 9. FIG. 10 illustrates avariation of the plug 52 having a substantially rounded or sphericalshape, as well as an outward flaring of the distal opening 54 in thefluid delivery conduit 22.

Turning to FIGS. 11-12, the medical device may include a mechanism orcomponent(s) providing selective deformation or externally-actuatedrestriction of a length of the fluid delivery conduit 22 to modify thefluid flow characteristics therethrough. For example, as shown in FIG.11, a deformation element 56 may be movably positioned within a portionof the medical device 12, and further operable to apply a depressibleforce onto an exterior surface of the fluid delivery conduit 22 to kinkor otherwise decrease the passable area, and thus fluid flow capacity,through the affected segment of the fluid delivery conduit 22. Thedeformation element 56 may include a sufficiently-rigid protrusion thatis controllably movable within the medical device 12 along asubstantially linear path transverse to the fluid delivery conduit 22through the use of one or more steering or actuator wires ortransmission linkages (not shown) accessible to a user at a handle orproximal end 18 of the device 12. As shown in FIG. 12, the deformationelement 56 may include a rotatable component that contacts the fluiddelivery conduit 22 at two locations in opposite directions to restrictor kink a portion of the conduit to affect fluid flow therethrough to adesired degree.

Fluid flow may further be controlled through the implementation of oneor more rotational components disposed within or about the fluid flowpath through the delivery conduit. For example, referring to FIG. 13,the fluid delivery conduit 22 of the medical device 12 may include asemi-circular or rounded flange 58 disposed on a distal end thereof andcircumscribing a portion of a fluid outlet 60 of the delivery conduit22. The fluid delivery conduit 22 and the flange 58 may be rotatablewithin the elongate body 16, and the fluid outlet 60 may be off-centerwith respect to a central longitudinal axis of the elongate body 16 ofthe medical device 12. A stopper 62 may be at least partially disposedwithin the elongate body 16 such that rotation of the fluid deliveryconduit 22 about the fixed stopper 62 increases or decreases thepercentage of the fluid outlet 60 that is unobstructed by the stopper62, thus modulating the fluid flowing therethrough. The rotation of thefluid delivery conduit 22 may be controlled at a proximal portion of themedical device 12, as described in more detail below, while the flange58 aids in securing the relative position of the fluid outlet 60 withrespect to the stopper 62 and/or wall of the elongate body 16. Turningnow to FIG. 14, the medical device may include a pivotable or rotatablevalve 64 disposed within a portion of the fluid delivery conduit. Thevalve 64 may be selectively opened or closed to a desired degree topermit or obstruct fluid flowing through the delivery conduit.

A rate or volume of fluid flowing through the medical device 12 mayfurther be controlled through selective opening or closing of all orpart of a plurality of openings or fluid dispersion points within themedical device 12 o selectively control the amount, direction, location,size, and/or other characteristics of the dispersion area. In thermaltreatment procedures, such fluid control provides the ability todirectly control the resulting location, size, and other characteristicsof the tissue treatment pattern. For example referring to FIGS. 15-16,the fluid delivery conduit 22 may define a plurality of fluid openingsor outlets 66, which may be positioned adjacent to thethermally-transmissive region 46 of the medical device 12. An elongatebody or rod 68 may be slidably positioned within the delivery conduit 22to selectively obstruct one or more of the outlets 66. For example, inFIG. 15, the rod 68 may be sufficiently dimensioned or sized to obstructall of the outlets in a first position, while being movable proximallyto a second position to uncover or otherwise allow fluid to flow out ofa one or more of the outlets 66, thus increasing fluid flow. In FIG. 16,for example, the elongate body or rod 68 may have a distal plug 70 sizedor dimensioned to only obstruct, at most, a portion of the fluid outlets66. In this example, the distal plug 70 may be selectively moved toprovide spatial control over the fluid dispersion out of the fluiddelivery conduit, e.g., either more-proximally or more-distally. Theplurality of fluid outlets 66 may include one or more spaced subsets ofoutlets having a predetermined separation distance between them toachieve a desired spatial separation between the selectable locationsfor dispersion, and thus the resulting thermal characteristics fortreatment or diagnosis.

One or more of the fluid outlets 66 may also include a directional taperor angular orientation, as shown in FIG. 17, such that selectiveobstruction of the fluid outlets 66 provides directional control overthe resulting fluid dispersion. Such directional control may beimplemented for example, when the thermally-transmissive region includesa balloon, and it is desirable to focus thermal exchange on a proximalportion of the balloon (for example, when directing treatment ordiagnosis towards a pulmonary vein or other proximally-located tissue)or a distal portion of the balloon (for example, when directingtreatment or diagnosis towards a septal wall or otherdistally-positioned tissue region). The directional dispersion may alsobe implemented with other thermally-transmissive regions, such aselongated, linear segments and other geometric configurations, forexample.

Aside from and/or in addition to providing selective fluid dispersion ina proximal-distal range, the medical device may also provide selectiveradial or rotational dispersion of the fluid either separately or incombination with the proximal-distal range to provide a variety oflongitudinally and radially controllable dispersion patterns. Forexample, referring to FIG. 18, the fluid delivery conduit 22 may includea dispersion manifold 72 along a length thereof, such as adjacent to thethermally-transmissive region of the device 12. The dispersion manifold72 may define a plurality of openings 74 positioned around itscircumference at different radial or angular positions. A rotationalselector element 76 may be rotatably movable with respect to thedispersion manifold 72 to selectively disperse fluid from the fluiddelivery conduit 22 out of a selected portion of the plurality ofopenings 74. The rotational selector element 76 may include, forexample, a sleeve having one or more openings at one or more selectradial positions such that when the openings in the rotational selectorelement 76 are aligned with a subset of the openings in the dispersionmanifold 72, fluid is directed outward in one or more specific, selectedradial directions. Though the rotational selector 76 is illustrated inFIG. 18 as being positioned within the dispersion manifold 72, it iscontemplated the rotational selector 76 may also be on the exterior ofthe dispersion manifold 72 and achieve the same selective dispersionwhen the openings are aligned. The rotational selector element 76 may beactuated or otherwise controlled with one or more wires, rods or thelike extending through the medical device 12 and accessible to a user.

Turning now to FIG. 19, the medical device may provide for selectivefluid dispersion to create either a smaller-area, focal or “spot”-typelesion, or a more elongated thermal treatment pattern. For example, themedical device may include a first thermally-transmissive segment 78having a first geometric configuration and a secondthermally-transmissive segment 80 having a second geometricconfiguration. The two regions may be spaced apart or substantiallyadjacent to one another. In a particular example, the firstthermally-transmissive segment 78 may include a distal tip providing a“spot”-type footprint or contact area, while the secondthermally-transmissive segment 80 may include an elongated segmentproviding a linear or curvilinear footprint or contact area. The fluiddelivery conduit 22 may again include a dispersion manifold 82, whichextends along a length of the second thermally-transmissive segment 80and defines one or more fluid outlets 84 longitudinally and/orrotationally spaced from one another. The device 12 may include adispersion selector 86 movably coupled to the manifold 82 to selectivelydisperse fluid either towards the first thermally-transmissive segment78 or the second thermally-transmissive segment 80. For example, thedispersion selector 86 may define a sleeve or secondary manifoldslidably and/or rotationally movable with respect to the dispersionmanifold 82. The dispersion selector 86 may define one or more primaryopenings 88 that are alignable with one or more of the fluid outlets 84of the dispersion manifold 82 when in a first position, thus directingfluid flow towards the second thermally-transmissive segment 80. Thedispersion selector 86 may further define one or more secondary openings90 that are positionable to disperse fluid towards the firstthermally-transmissive segment 78 when in a second position. The secondposition may also include a misalignment between the primary openings 88and the fluid outlets 84 of the manifold 82 such that fluid is preventedfrom being dispersed towards the second thermally-transmissive segment80. The secondary opening(s) 90 may be positioned on a distal end orregion of the dispersion selector 86 that extends out of the manifold 82in the second position, while being contained within the manifold 82when the selector 86 is in the first position. There may be a seal orgasket (not shown) between the selector 86 and the manifold 82 allowingtelescoping movement while restricting fluid flow to one or more of theoutlets rather than between a gap or opening between the manifold 82 andthe selector 86 themselves, for example.

As shown in FIGS. 16-19, one or more of the components described above,e.g., the manifold 72,82 or selectors 76,86, may have at least oneradiopaque marker 92 to aid in identifying and manipulating a positionand/or alignment of the fluid delivery components to achieve a desiredrotational and/or longitudinal position and associated fluid flow ordispersion characteristics. FIG. 20 illustrates an additional example ofa radiopaque marker 92 that is angularly positioned asymmetrically on adispersion tube (which may include any of the manifolds or componentsdescribed herein) to selectively direct fluid flow to one or moreregions of the thermally transmissive region 46, which in this exampleincludes a balloon or expandable element.

Turning now to FIGS. 21-22, examples of the medical device 12 are shownproviding selective and/or movable thermal insulation about at least aportion of the thermally transmissive region 46 to provide a desiredtreatment or diagnosis pattern. For example, the medical device 12 mayinclude one or more insulators 93 movably coupled to the thermallytransmissive region 46 that prevent or significantly reduce energyexchange with the thermally transmissive region 46 and the surroundingenvironment or targeted tissue, while controllably exposing otherportions of the region 46 to interact, diagnose, and/or treat a tissueregion. The insulators 93 may be oriented and movable in aproximal-to-distal direction, as shown in FIG. 21, or the insulators 93may be oriented and movable around a radial circumference of thethermally transmissive region, as shown in FIG. 22. The insulators maybe constructed from a thermally-insulating material that is sufficientlyconformable or flexible to facilitate coupling to the thermallytransmissive region and/or other portions of the medical device, such asthe elongate body 16. The controllable movement of the insulators may beaccomplished through the use of one or more pull wires or otheractuation elements (not shown), and may be further facilitated by one ormore joints, hinges, or the like providing a range of movement about thethermally-transmissive region

Returning again to FIG. 1, the medical device 12 may include a handle 94coupled to the proximal portion of the elongate body 16. The handle 94can include circuitry for identification and/or use in controlling ofthe medical device 12 or another component of the system. For example,the handle 94 may include one or more pressure or flow rate sensors 96to monitor the fluid pressure and/or flow rate within the medical device12. Additionally, the handle 94 may be provided with a fitting 98 forreceiving a guide wire that may be passed into a guide wire lumen. Thehandle 94 may also include connectors 100 that are matable directly to afluid supply/exhaust and control unit 14 or indirectly by way of one ormore umbilicals. The handle 94 may further include blood detectioncircuitry in fluid and/or optical communication with the injection,exhaust and/or interstitial lumens. The handle 94 may also include apressure relief valve in fluid communication with the fluid deliveryconduit 22 and/or exhaust lumen 24 to automatically open under apredetermined threshold value in the event that value is exceeded.

The handle 94 may also include one or more actuation or control featuresthat allow a user to control, deflect, steer, or otherwise manipulate adistal portion of the medical device from the proximal portion of themedical device. For example, the handle 94 may include one or morecomponents such as a lever or knob 102 for manipulating the elongatebody 16 and/or additional components of the medical device 12, such asthe selectors, manifolds, or other fluid flow components describedherein. Movement or operation of these components may be triggered orperformed mechanically, electro-mechanically, and/or in conjunction withone or more sensors described herein to the provide a variety ofpredetermined configurations and/or fluid flow sequences or patterns.For example, a pull wire 104 with a proximal end and a distal end mayhave its distal end anchored to the elongate body 16 at or near thedistal portion 20, such as the distal insert 26. The proximal end of thepull wire 94 may be anchored to an element such as a cam incommunication with and responsive to the lever 102.

The medical device 12 may include an actuator element 106 that ismovably coupled to the proximal portion of the elongate body 16 and/orthe handle 94. The actuator element 106 may further be coupled to aproximal portion of the fluid delivery conduit 22, rod 50, 68, and/orselectors 76,86 such that manipulating the actuator element 106 in alongitudinal direction causes longitudinal manipulation of the attachedcomponent. The actuator element 106 may include a thumb-slide, apush-button, a rotating lever, or other mechanical structure forproviding a movable coupling to the elongate body 16 and/or the handle94. Moreover, the actuator element 106 may be movably coupled to thehandle 44 such that the actuator element is movable into individual,distinct positions, and is able to be releasably secured in any one ofthe distinct positions.

The medical device 12 may include one or more rotational controlelements 108 that are rotatably coupled to the proximal portion of theelongate body 16 and/or the handle 44. The rotational control element(s)58 may further be coupled to the proximal and/or distal ends of thefluid delivery conduit 22, rod 50,68, selectors 76,86, or other fluidflow control elements described herein such that rotating the rotationalcontrol element 108 about a longitudinal axis of the handle 44 and/orelongate body 16 results in similar rotation of the attachedcomponent(s) at the distal portion of the medical device 12. Therotational control element 108 may include a knob, dial, or othermechanical structure for providing a rotatable coupling to the elongatebody 16 and/or the handle 94. Moreover, the rotational control element108 may be rotatably coupled to the handle 94 and/or elongate body 16such that the rotational control element is movable into individual,distinct positions, and is able to be releasably secured in any one ofthe distinct positions.

The system 10 may further include one or more sensors to monitor theoperating parameters throughout the system, including for example,pressure, temperature, flow rates, volume, or the like in the controlunit 14 and/or the medical device 12, in addition to monitoring,recording or otherwise conveying measurements or conditions within themedical device 12 or the ambient environment at the distal portion ofthe medical device 12. The sensor(s) may be in communication with thecontrol unit 14 for initiating or triggering one or more alerts ortherapeutic delivery modifications during operation of the medicaldevice 12. One or more valves, controllers, or the other componentsdescribed herein may be in communication with the sensor(s) to providefor the automated and/or controlled dispersion or circulation of fluidthrough the lumens/fluid paths of the medical device 12. Such valves,controllers, or the like may be located in a portion of the medicaldevice 12 and/or in the control unit 14.

In an exemplary system, a fluid supply 110 including a coolant,cryogenic refrigerant, or the like, an exhaust or scavenging system (notshown) for recovering or venting expended fluid for re-use or disposal,as well as various control mechanisms for the medical system may behoused in the control unit 14. In addition to providing an exhaustfunction for the catheter fluid supply, the control unit 14 may alsoinclude pumps, valves, controllers or the like to recover and/orre-circulate fluid delivered to the handle, the elongate body, and/orthe fluid pathways of the medical device 12. A vacuum pump 112 in thecontrol unit 14 may create a low-pressure environment in one or moreconduits within the medical device 12 so that fluid is drawn into theconduit(s)/lumen(s) of the elongate body 16, away from the distalportion and towards the proximal portion of the elongate body 16. Thecontrol unit 14 may include one or more controllers, processors, and/orsoftware modules containing instructions or algorithms to provide forthe automated operation and performance of the features, sequences, orprocedures described herein.

Several of the above configurations and methods of use thereof providethe ability to modify the effective cross-sectional area of the fluiddelivery conduit available for fluid flow. Accordingly, selectivecontrol of these configurations allows fluid flow to be regulated asdesired while the fluid delivery pressure remains the same. Additionalconfigurations provided herein allow for the selective manipulation of afootprint or therapeutic pattern achievable with the medical deviceduring a single procedure, negating the need for the removal andinsertion of multiple devices to achieve the same variations intreatment geometry or characteristics. Moreover, while the medicaldevice 12 may be in fluid communication with a cryogenic fluid source tocryogenically treat selected tissue, it is also contemplated that themedical device 12 may alternatively or additionally include one or moreelectrically conductive portions or electrodes thereon coupled to aradiofrequency generator or power source of the control unit 14 as atreatment or diagnostic mechanism.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed herein above. In addition, unless mention was made above tothe contrary, it should be noted that all of the accompanying drawingsare not to scale. Of note, the system components have been representedwhere appropriate by conventional symbols in the drawings, showing onlythose specific details that are pertinent to understanding theembodiments of the present invention so as not to obscure the disclosurewith details that will be readily apparent to those of ordinary skill inthe art having the benefit of the description herein. Moreover, whilecertain embodiments or figures described herein may illustrate featuresnot expressly indicated on other figures or embodiments, it isunderstood that the features and components of the system and devicesdisclosed herein are not necessarily exclusive of each other and may beincluded in a variety of different combinations or configurationswithout departing from the scope and spirit of the invention. A varietyof modifications and variations are possible in light of the aboveteachings without departing from the scope and spirit of the invention,which is limited only by the following claims.

What is claimed is:
 1. A medical device, comprising: a catheter bodydefining a distal portion; a fluid delivery conduit defining an outletin the distal portion of the catheter body, and a deformation elementwithin the catheter body, the deformation element controllably movableto deform a portion of the fluid delivery conduit to affect fluid flowtherethrough.
 2. The medical device of claim 1, wherein the deformationelement is movable substantially perpendicularly to the fluid deliveryconduit to depress a portion of the fluid delivery conduit.
 3. Themedical device of claim 1, wherein the deformation element issubstantially rigid.
 4. The medical device of claim 1, wherein thedeformation element is operable from a proximal end of the medicaldevice.
 5. The medical device of claim 1, wherein the deformationelement is rotatable about the fluid delivery conduit to depress aportion of the fluid delivery conduit.
 6. The medical device of claim 5,wherein the deformation element contacts the fluid delivery conduit attwo locations.
 7. The medical device of claim 6, wherein rotating thedeformation element kinks the fluid delivery conduit.
 8. The medicaldevice of claim 1, further comprising a fluid supply in fluidcommunication with the fluid delivery conduit.
 9. The medical device ofclaim 1, further comprising a vacuum pump in fluid communication withthe catheter body.
 10. A method of regulating fluid flow through acatheter, comprising: delivering a fluid to a first conduit disposedwithin a portion of the catheter; and mechanically deforming a portionof the first conduit to controllably regulate fluid flowingtherethrough.
 11. The method of claim 10, wherein mechanically deformingthe first conduit includes depressing an exterior surface of the firstconduit in a direction substantially perpendicular to a direction offluid flow.
 12. The method of claim 10, wherein mechanically deformingthe first conduit includes rotating a deformation element about thefirst conduit to impart a kink.
 13. The method of claim 10, wherein anelongate member is disposed within the deformed portion of the firstconduit.
 14. The method of claim 10, wherein the fluid is a cryogenicrefrigerant.
 15. The method of claim 14, further comprisingcryogenically treating a tissue region with a portion of the catheter.16. The method of claim 10, further comprising evacuating at least aportion of the fluid from the catheter with a vacuum pump.
 17. Themethod of claim 10, wherein mechanically deforming a portion of thefirst conduit includes manipulating a deformation element from aproximal portion of the catheter.